Chemistry Anyone? Trivia Quiz

Answer: hydrogen

Noble gases are so called because they are very inactive at normal temperature and pressure. They do undergo chemical reactions, but under extreme conditions. There are six noble gases in all. They are neon, argon, xenon, radon, krypton and helium. Hydrogen is the first element in the periodic table and has accumulated in the atmosphere due to its unreactive nature.

Answer: iridium

Iridium has a density of 22.61 g/cc followed by osmium which is at 22.57 g/cc. Iridium has an atomic number 77 and is placed in the sixth period and ninth group of the modern periodic table.

Answer: true

Bromine is placed in the seventeenth group and fourth period of the modern periodic table. It is a member of the halogen group. It is a heavy, volatile reddish brown liquid and produces painful sores when spilled on the skin.

Answer: oxygen

The most abundant element in the Earth's crust is oxygen which occupies 46.4% of the Earth's crust. silicon, aluminium and iron occupy 28.2%, 8.32% and 5.63% of the Earth's crust, respectively.

Oxygen is a Period 2 and Group 16 element occupying 21% of the Earth's atmosphere. It is a colorless gas and exists as a pale blue liquid. Oxygen is the third most abundant element found in the sun after helium and hydrogen and it plays a part in the carbon-nitrogen cycle. Mars contains .15% of oxygen. Ozone, an allotrope of oxygen shields the Earth from the harmful UV rays.

Figures courtesy: http.//www.webelements.com/webelements/

Answer: Elements of the second period

Elements of the third period are called typical elements because they have characteristic properties of the group they belong to. Elements of the first and second group are called alkali metals and alkaline earth metals, respectively.

Period: The modern periodic table is divided into seven horizontal columns known as periods.

Group: The modern periodic table is divided into eighteen vertical columns known as groups.

Answer: black

Phosphorus exists in mainly three allotropic forms which are black, white and red. Black is the most stable and white is the most unstable. Yellow phosphorus is mainly a mixture of white and red Phosphorus.

Allotropy: The property that certain chemical elements and compounds have of existing in two or more different forms is called allotropy. Sulphur has the most allotropes followed by carbon.

Answer: tungsten

Pure tungsten metal is a steel-gray to white metal. It has a melting point of 3653K. Due to this property it is used as filaments in electric bulbs. It oxidizes in air and must be protected at elevated temperatures. due to its unreactive nature.

Vapor pressure: The pressure exerted by a vapor in equilibrium with its solid or liquid phase.

Answer: boron carbide

Boron carbide or norbide is the hardest artificially prepared substance and is also a very good conductor of electricity. Due to its high hardness, boron carbide powder is used as an abrasive in polishing.

Answer: radium

Pure radium is whitish in color, but turns black after sometime due to formation of radium nitrite. Radium is over a million times more radioactive than the same mass of uranium.

Radioactivity: The property of an element to spontaneously emit highly penetrating radiations and undergo self disintegration is called radioactivity.

Answer: astatine

The longest-lived isotope, of mass number 210, has a half-life of 8.3 hours. There are about 20 isotopes known, all of which are radioactive, having very short half lives. Astatine is a halogen and accumulates in the thyroid like iodine.

Figures courtesy: http://www.webelements.com/webelements/